Coat Color Genetics of Borzoi and Silken Windhounds

The Coat Color Genetics of Borzoi

This page is a collaboration between Ashley Cirimeli and Danielle Steenkamp (Satara Borzoi). We will primarily focus on Borzoi but will include some Silken Windhound examples too. These two breeds have a fantastic rainbow of colors in their respective gene pools, and we have only scratched the surface of understanding what causes what. We have put together this page as a reference/guide for anyone interested in the magic of color genetics.

If you learn something, consider buying me a cup of coffee!

First and foremost, this page will use genetic color terms as opposed to breed color terms. There has been some confusion with the varying names (grizzle vs sable vs sabled, for example). Below is a chart that will list genotype, breed term, and genetic term. Where a genetic term for a specific color combo doesn’t exist, breed terms will be used instead. When we say "sable", we are speaking of the Ay allele (think collies and shelties), not Eg modifying Black and Tan (what borzoi folks call Sable).

Genotype	Genetic Term	Borzoi/Silken Term
KB	Dominant Black	Dominant Black
Kbr	Brindle	Brindle
ky	non-domonant black	-
E	Normal Expression	-
Em	Mask	Mask
eg	Grizzle	Sable
e/e	Recessive Red	Gold / black suppressed cream
Ay	Sable	Sabled [red intensity]
at	Black and Tan	Black and Tan
KB/- Eg/Eg Ay/-	-	Chinchilla/Silver
KB/- Eg/Eg at/at	-	black and silver

Genetic Jargon Explained

As you read this page, you'll see a lot of words that may be unfamiliar, like homozygous, allele, locus, dominant, etc. Here is a handy guide to help!

Locus: A locus refers to the location on the chromosome where the gene is found. Example: black and tan, at/at is on the A locus
Allele: Alleles are variants of the same gene that occur on the same place on a chromosome. Example: at/at, Ay, and aw are all alleles on the A locus.
Homozygous/Heterozygous: Zygosity is the degree of similar traits in an organism. The prefixes homo and hetero respectively mean same and different. Example: at/at is homozygous whereas Ay/at is heterozygous.
Eumelanin: Black pigment
Phæomelanin: Red pigment
Dominant/Recessive: Brindle for example, is a dominant allele, meaning a dog only needs one copy of the allele in order to express the color/pattern (Kbr/-). Black and tan is a recessive allele; a dog needs two copies in order to express black and tan (at/at). We use capitals and lower case letters to differentiate between dominant and recessive alleles. On the A locus, at, aw, and a are recessive while Ay is dominant.
There is also a hierarchy of dominant and recessive alleles on each locus. On the K locus, both dominant black (KB) and brindle (Kbr) are dominant alleles-- the dog only needs one copy to express the color/pattern. However, what happens when a dog is KB/Kbr? Both are dominant alleles, but KB is dominant to Kbr, therefore the dog will be black.
Genotype: The genetic constitution of an organism.
Phenotype: The observable characteristics of an organism.

Color Guide

Dogs contain two pigments that influence their color: Eumelanin (black) and Phæomelanin (red). There are genes that can modify/dilute these pigments to look like a whole host of other colors (silver, liver, blue, etc.). White isn’t a pigment, but rather the absence of pigment.

It’s easy to comprehend canine colors when thinking about them in terms of layers. White is the top most layer, then black, then red. White hides all, black hides red. Think of white like a blanket that falls on top of everything else. Holes in the white (caused by any number of genes such as piebald or ticking) will show the color that exists underneath. Sometimes that white blanket is small and only shows up as a few hairs on the chest, or a blotch over the toes. Sometimes it covers the entire dog.
Similarly, holes/breaks in black will reveal the red underneath (black and tan, brindle, etc.).

The color of the dog still exists underneath the white! So you will still see the markings underneath if there are holes/breaks (spots) in the white pattern. In this example, you can still see the black and tan markings!

The White Series

MITF and White Spotting in Dogs: A Population Study

Only the sp allele (spotting) has been identified on the S locus, so other white patterns will all test as S/S.

S/S - Solid or Self most likely. No white expressed. Some dogs that are S/S can still have white markings due to what is called "Residual White". The white is usually on the chest, toes, and tip of the nose. Residual White occurs when pigment doesn't migrate fully as the embryo develops. Additionally, a true Irish marked borzoi (the same gene that causes Irish markings in herding breeds like border collies) will test as S/S.

S/sp - The combination of Solid/Self and Piebald alleles can often create what looks like Irish markings, called “pseudo Irish”, however there is quite a big range in how these white markings phenotype. S/sp can range from what looks like a Solid dog with minimal white (self), to a flashy Irish with a full white collar.

sp/sp - Piebald. This is a recessive allele and requires two copies in order to express. Piebald typically appears as random spots on the body and can range from heavy colored to what is called "extreme piebald", in which the dog only has pigment on the ears and/or eyes.

The K Locus

KB/- - Dominant Black. Because it's a dominant allele, a dog only needs one copy in order to express. In most cases, a dog carrying one copy of the Dominant Black allele will only appear black (aside from white patterns). The exceptions to this would be liver (b/b), blue (d/d), sometimes grizzle (eg), recessive red (e/e) and ghost tan (unknown locus/allele). These alleles all modify, dilute, or hide the eumelanin in different ways.

Kbr/- - Brindle. Brindle is a dominant allele, but it is recessive to dominant black. While we write the brindle allele as “Kbr” for ease, every brindle dog will test as “KB/ky” because brindle is the result of a duplication of the KB and ky alleles. Pheomelanin is expressed where there are breaks in the black pattern, creating a striped look. The width of these breaks can vary. Any allele(s) that dilutes or modifies black or red pigment will alter the color/appearance of the brindle; for example: above right, silver brindle. Genes that modify phæomelanin can similarly alter the look of a brindle dog.

ky/ky - wild type, or non-dominant black. This is the most recessive allele on the K locus, and does not alter appearance. A dog that is homozygous for ky will not express dominant black or brindle, but instead express whatever other alleles are present on loci E, A, D, B, and S. They can still express eumelanin in their coats from the A and E loci, and will likely still have dark pigment on their nose and eyes.

The E Locus

Em/- - Mask. The Mask allele is the most dominant on the E locus. Masking describes the eumelanin on the face of the dog. It can range from just a small bit around the nose to a full face. In some breeds, masking can extend beyond the head! This is commonly referred to as “extreme masking”.

eg/- Grizzle. Grizzle is not a specific color or pattern but rather an allele that modifies other colors and patterns. It is Recessive to Em, and E, but dominant to e. In salukis, grizzle is dominant to E.
Please scroll down to read more about the wonderful ways of grizzle.

e/e - Recessive Red. Recessive Red completely eliminates all black hair pigment except for somatic mutations. Sometimes it can affect the pigment of the skin on the nose, lips, and eyelids too. The intensity of this red can vary from almost white to a rich dark red/brown. It can be tricky to differentiate between recessive red and clear sable. Usually clear sables will have at least some black whiskers while recessive reds will have no black hairs at all, unless they express somatic mutations.

E/- - Extension. The Extension allele does not appear as a specific color or pattern, similar to ky. E is recessive to Em, but dominant to eg and e-- meaning a dog who is E/eg will not show the effects of grizzle and instead will show whatever color/pattern they have on the A locus, and/or K locus. When testing dogs, E is the "process of elimination" allele. When a dog tests negative for Em, Eg, and e, labs will list results as E.

The A Locus

Ay/- - Sable. Sable is an interesting allele that has a wide range of phenotypes. Sometimes sable can look very similar to one of the Grizzle patterns (a sharp widow's peak with a blanket of black across the body). Sometimes it can simply be small areas of black on the tail and neck. And sometimes it can be no black at all, AKA "Clear Sable". The Sable hairs are banded, meaning they are red at the root and black at the tips (when eumelanin is expressed). Heavily shaded sables will develop their shading as they mature and are often closer to clear sable as puppies.

at/at - Black and Tan. This is a recessive allele; a dog must be homozygous in order to express black and tan (there are some exceptions in other breeds that have wolf grey and recessive black). This is the same pattern seen in breeds like Doberman Pinscers, Rottweilers, and Bernese Mountain Dogs.

Additionally on the A locus are the aw (wolf sable) and a (recessive black) alleles. Neither of these alleles are in the borzoi or silken gene pools. Wolf sable is seen in chart polski.

Liver and Blue

Liver/Chocolate/Brown - b/b. Liver affects any eumelanin and changes it to a red/brown color. Any black skin pigment, such as on the lips, eyelids, and nose leather, will be similarly brown in color. Eyes are typically a more yellow-ish color. B/B (capital letters) indicates no presence of liver, and all pigment will be black. Some have mentioned seeing liver borzoi in the past but I have yet to see evidence of it existing in borzoi. It should be noted that blue dilute can look deceptively like liver on some dogs such as Ay sable. If you have a borzoi or silken that has tested B/b or b/b, please let me know!

Blue/Dilute - d/d - Like liver, dilute will affect any eumelanin and dilutes it to a grey color (including nose, eyelid, and lip pigment). Eyes will be more of a yellow color. Sometimes the pigment will be dark enough that the dog will appear to be a typical silver. However, in bright sunlight and next to a dog with dark black pigment, it is more noticeable. In some breeds, hair loss is associated with dilute (called Canine Dilute Alopecia), but there hasn’t been evidence of this existing in Borzoi or Silken Windhounds. D/D (capital letters) indicates no presence of dilute. Dilute is quite rare in borzoi.

The Wonderful Ways of Grizzle

Grizzle, eg, truly deserves its own section in a color break down because it has such a broad influence over other alleles. In some cases, eg restricts pigment and modifies the pattern (black and tan). In other cases, it seems to dilute both eumelanin and pheomelanin. Through coat color genotype testing in Borzoi, Silkens, Salukis, and Afghan Hounds, we have come to better understand the unique ways in which this allele can interact with other genes.
What we have concluded is that the phenotype of a homozygous eg hound depends entirely on what is happening on the K locus and A locus. If the dog is E/eg or Em/eg, then Grizzle will not affect the other loci, and the dog will not express any of the various grizzle looks below.

Classic Grizzle - ky/ky eg/eg at/at - Alternatively can be eg/e. In this instance eg is modifying at/at, black and tan. The black markings recede a bit to create a widow's peak on the face, and a dark blanket of black covering the rest of the body. The black hairs are banded-- the tips are black while the roots are red. eg doesn't dilute eumelanin in this instance, but can dilute pheomelanin. A dog that would otherwise be a dark, rich, Irish Setter type red will typically lighten to tan, tans lighten to cream, and creams lighten to create what borzoi folk call "silver sable" (ahem, grizzle).

Cream/Clear Sable - ky/ky eg/eg Ay/- - When grizzle affects the Ay allele, it makes any black markings recede, similarly to how classic grizzle makes the at/at black markings recede. So much so that any remaining eumelanin is typically only visible on the ear tips, with a silvery look. Puppies with this genotype are often born with silvery markings that fade over time. This genotype can be hard to differentiate from recessive red, e/e, because there are sometimes no black hairs to be found, even on the whiskers. Note, this isn’t the only genotype for solid creams or lighter pheomelanin. Some sables without eg can be clear and have light phæomelanin, as well as the aforementioned recessive red.

Brindle Grizzle - Kbr/- eg/eg at/at - Just like classic grizzle, but with the added bonus of brindle. In this instance, the brindling will only appear in areas that are tan.

Silver Brindle - Kbr/- eg/eg Ay/Ay - When the A locus is sable instead of black and tan, all eumelanin on the K locus becomes diluted. As such, the brindle stripes become a silver color. Because grizzle dilutes pheomelanin as well, the end result can sometimes look like a silver dog with slightly darker silver stripes. With darker pheomelanin, the dog might instead appear to have silver stripes on a more cream/gold base.

Silver/Chinchilla - KB/- eg/eg Ay/Ay - Similar to silver brindle, but with dominant black on the K locus instead of brindle. Some silver/chinchilla dogs will look very black while others look like a much lighter silver color. The darkness of eumelanin seems to depend on how much black is expressed in their sable (Ay). Dogs that would otherwise be shaded sable end up much darker silver/chinchilla. Clear sables end up being a much lighter silver color. In some cases, eg doesn’t dilute phæomelanin, and the dog will have an interesting look of a brick red smudged together with black.

Black and Silver - KB/- eg/eg at/at - Just like with Silver/Chinchilla, eg dilutes eumelanin from the K locus but leaves eumelanin from the A locus mostly untouched. This genotype is almost identical to classic grizzle, save for the addition of dominant black (KB). Instead of modifying at/at to create a widow’s peak marking, dogs retain their at/at markings but with silver instead of tan. Sometimes varying degrees of phæomelanin remains on legs. Interestingly enough, as dogs with this genotype grey with age, it appears to first affect the cheeks and pips, but then follows the classical grizzle pattern, eventually creating that widow’s peak.

Oddities/Misc

This Silken displays an interesting example of brindle, in which the striping appears more "blotchy", almost resembling Merle.

Photo Examples

Dominant Black

Photo by Kristen Suhrenbrock of Lightning, bred/owned by Jamie Bobrowski

Brindle (red pigment is mahogany color)

Photo by Ashley Siemon

Bindle (red pigment is cream color)

Photo by Ashley Siemon

Silver Brindle - Kbr/- Eg/Eg Ay/Ay

Photo by Ashley Siemon

Sable (Ay/-) This is a good example of sable (reminder: not what borzoi/silken folk call sable) without heavy shading. A clear sable would not have the black markings around the ears and neck. A heavily shaded sable would have a lot more black along the back and head.

Photo by Ashley Siemon

Kbr/ky Em/- Ay/- Here is a good example of how shaded sable (reminder: not the same as breed terminology sable) interacts with brindle. Dogs are born lighter, and develop heavy shading as they mature, but this time with the addition of brindle striping. This dog is also masked.

Photos by Kristen Suhrenbrock